This invention is concerned with a plumbing sleeve suitable for connecting to a toilet, or other relatively fixed installation, placed on a concrete floor.
In many buildings and similar structures concrete floors are used to which various plumbing fixtures, particularly toilets, have to be attached. Generally speaking, a piping connection will extend substantially vertically downwardly through the floor, thus connecting the toilet or other fixture above it to a sanitary or sewer main below it. It is usual practice to place the piping connection in position before the concrete comprising the floor is poured and allowed to set into place around it, inherently securing the piping connection in place. However, once the concrete has been poured and has set, any adjustment to the piping connection becomes impossible. This is particularly important for a toilet, where a sanitary connection is absolutely necessary. Once any flange or cap has been placed, and the cement set, it is effectively immovable. On the other hand, it is extremely difficult to pour concrete for a floor to an exact and predetermined height. In other words, when placing such a piping connection it is almost impossible to predetermine with sufficient accuracy to guarantee the required sanitary joint exactly where that joint is going to be.
There are two types of concrete floor or other surface which have to be considered: those where there is a free space below, such as an intermediate floor in a high-rise building, and those where there is no free space below, such as a slab placed on grade. Floors with a space below them are poured, generally, onto some form of supported wooden shuttering. Various proposals have been made to facilitate placement of a vertical sanitary, drain or sewer pipe in such floors. Morell, in Canadian Patent 680,724 describes a pipe sleeve structure which is essentially a short tube having a radially outwardly extending flange at one end. The sleeve is of flexible plastic, the flange has a plurality of centering openings and the tube has a length less than the thickness of the floor to be laid. In use, the sleeve is nailed to the wood shuttering, and thus appears to serve primarily to locate the position of the desired hole. A conventional pipe is placed into the short tube. Morell is silent as to what happens to the sleeve when the shuttering (to which it is nailed) is removed. A similar device is described by Hagedorn in Canadian Patent 767,536.
A more complex arrangement is described by Cornwall in Canadian Patent 1,162,21. In this coupling, a three part system is used comprising a coupling part which is at least temporarily supported by the shuttering. Conventional piping is inserted from both above and below, to the top end of which is attached a suitable fitting, for example to attach a toilet thereto. Again, the coupling is nailed in place onto the shuttering, and the upper fitting placed thereon before the floor is poured.
Thus none of these devices appear to address the problem of floor thickness variation, nor do they appear to be applicable to a slab which is not poured onto shuttering. It is thus apparent that a need exists for a simple pipe sleeve unit which can be used in concrete floors which are not poured onto shuttering. Advantageously such a sleeve should also be amenable to use in situations where shuttering is used.